Strong graded interface related piezoelectric polarization weakening effects on exciton confinement in single InxGa1−xN/GaN quantum wells

✍ Scribed by E.W.S Caetano; V.N Freire; G.A Farias; E.F da Silva Jr.

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 168 KB
• Volume: 13
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/s1386-9477(02)00314-4

✦ Synopsis

We consider how the weakening of piezoelectric polarization e ects due to the existence of graded interfaces modiÿes the conÿned exciton properties in In0:2Ga0:8N=GaN single quantum wells. The balance between the red shift of the exciton energy related to the enormous polarization electric ÿeld inside the well, and its strong blue shift resulting from the existence of graded interfaces as thin as three monolayers, is shown to be important. We conclude that a better interface characterization is more fundamental to better estimates of the conÿned exciton energy in InxGa1-xN=GaN quantum wells than an improved knowledge of the carriers e ective masses and the band o set in actual samples.